The rush to expand crude oil transportation to and around the U.S. Gulf Coast has triggered conflict between some major and independent midstream operators.

Several claims before the Texas Railroad Commission, which has jurisdiction over pipelines in the state, accuse big operators of not allowing independents the open connections that are required under common carrier rules. A ruling in one case is expected in April, but there are many more disputes that have not made it to formal regulatory filings.

Industry observers suggest that while spats over interconnection are endemic in the midstream, the number and size of the current disagreements reflect fundamental changes in the first and last miles of projects. Not too many years ago trunk-line operators were reluctant to get involved in the first mile of gathering, and were mixed on interest in the last mile. The bust of the shale bonanza changed all that.